On the spectral domain approach to long-range propagation of high-frequency waves along a strip conductor above a PEC surface

TL;DR

This paper develops a spectral domain approach to analyze high-frequency wave propagation along a metallic strip above a PEC surface, providing methods for both narrow and wide strips with applications to power and railway systems.

Contribution

It introduces a mode matching and Chebyshev polynomial expansion method for arbitrary strip widths and an approximate longitudinal current method for narrow strips, useful for layered wire structures.

Findings

The full wave mode matching approach accurately models wave propagation.

The approximate method is effective for narrow strips and layered structures.

Potential applications include power lines and railway wire systems.

Abstract

A generic problem of high frequency wave propagation along a metallic strip in parallel above a PEC ground plane is considered. The wave is excited by an elemental electric dipole at an arbitrary location above the PEC plane. The full wave problem, for arbitrary widths of the strip, is solved by means of a mode matching approach and expansion of the strip surface current into Chebyshev polynomials. For narrow strips, an approximate method using only longitudinal currents is derived, and compared numerically with the full wave method. Utilizing the concept of equivalent radius, the approximate method for narrow strips is evaluated numerically against results for thin circular wires. It is concluded that the approximate method is suitable for handling multiple wires in layered structures, wherefore the method has potential usefulness for estimating long range propagation of high frequency waves in wire structures like power lines and railway feeding systems, containing over-head wires and wires submerged into ground.